Esophageal strictures: Management beyond dilation

Abstract

Esophageal stricture refers to a pathological narrowing of the esophageal lumen, causing dysphagia and impairing the patient's quality of life. There are various etiologies including esophageal malignancy, peptic injury, caustic ingestion, post-surgical anastomosis, radiation therapy, and inflammatory disorders such as eosinophilic esophagitis. The primary goal in managing esophageal strictures is to relieve dysphagia by maintaining luminal patency. Endoscopic dilation remains the mainstay of treatment for most benign strictures, with either bougie or balloon dilators. For patients who develop refractory or recurrent strictures that are difficult to manage with dilation alone, adjunctive therapies like intralesional steroid injections, topical or injected mitomycin C, incisional therapy, stent placement, and finally surgery may enhance outcomes and reduce the frequency of repeat procedures. The present review focuses on the basics of dilation and adjunctive strategies for the management of esophageal stricture.

Key Words: Benign esophageal stricture; Refractory esophageal stricture; Intralesional steroids; Mitomycin C; Self-expanding metal stent; Incisional therapy; Stricturoplasty; Peroral endoscopic tunnelling and restoration of the esophagus; Self-dilation

Core Tip: Esophageal strictures are managed by dilation, and most often, they respond depending on the etiology of the stricture. At times, when a stricture evolves into a refractory or recurrent stricture, management requires additional techniques and devices to successfully maintain a desired diameter to avoid dysphagia for optimal clinical success. The other aim is to maintain a satisfactory luminal diameter for an adequate duration once the target diameter has been achieved. In this mini-review, we discuss the management of esophageal strictures beyond dilation and deliberate the use of drugs, techniques, and devices for their management.

INTRODUCTION

Esophageal stricture refers to a pathological narrowing of the esophageal lumen. Esophageal strictures are a common cause of dysphagia and can significantly impair a patient's quality of life (QoL)[1]. They may arise from various etiologies, including esophageal malignancy, peptic injury, caustic ingestion, surgical anastomosis, radiation therapy, and inflammatory disorders such as eosinophilic esophagitis[2,3]. The primary goal in the management of esophageal strictures is to relieve dysphagia, maintain luminal patency, and minimize the need for repeated interventions. Endoscopic dilation remains the mainstay of treatment for most benign strictures, with either bougie or balloon dilators[3].

However, some patients develop refractory or recurrent strictures that are difficult to manage with dilation alone[3]. In such cases, adjunctive therapies – including intralesional steroid injections, topical or injected mitomycin C, incisional therapy, and stent placement – may enhance outcomes and reduce the frequency of repeat procedures[4]. The choice of treatment depends on multiple factors. Emerging evidence continues to refine the optimal approach to manage refractory esophageal strictures. The present mini-review focuses on the basics of dilation and adjunctive strategies for the management of esophageal stricture.

ETIOLOGY OF ESOPHAGEAL STRICTURE

The development of strictures is typically the result of chronic inflammation and subsequent fibrosis, which can arise from a variety of underlying causes. Broadly, esophageal strictures can be classified as benign or malignant, and accurate differentiation is crucial, as the management strategies differ significantly. Table 1 categorises the various benign causes of esophageal stricture.

Table 1 It enumerate various benign causes of esophageal stricture.

Intrinsic esophageal disorders	Iatrogenic or accidental
Peptic esophagitis	Postsurgical-anastomotic
Eosinophilic esophagitis	Post-radiation therapy
Miscellaneous disorders of the squamous epithelium (e.g., scleroderma, epidermolysis bullosa dystrophica, pemphigus and pemphigoid, lichen planus)	Endoscopic therapy; post endoscopic resection-endoscopic mucosal resection/endoscopic submucosal dissection; radiofrequency ablation; variceal band ligation
Motility disorders (e.g., achalasia)	Long-term nasogastric feeding tubes
Rings and webs (e.g., Schatzki ring)	Caustic ingestion

Malignancy remains the most critical cause of esophageal stricture and dysphagia, most commonly resulting from advanced esophageal or gastroesophageal junction cancers. Unlike benign strictures, malignant ones are generally not managed with routine endoscopic dilation due to the significant risk of perforation. Instead, the primary approach remains definitive surgery or chemoradiation. Only as a palliative care, self-expanding metal stents (SEMS) are placed to relieve dysphagia and restore oral intake[5]. Endoscopic dilation may be performed in select cases, but its role is limited – typically used only to allow the passage of a stent delivery system or feeding tube. In such scenarios, dilation is done cautiously, usually not exceeding a diameter of 5-7 mm.

Among the benign causes, the most common etiology in the past was peptic injury due to longstanding gastroesophageal reflux disease[2,3]. However, the incidence has declined with the widespread use of proton pump inhibitors (PPI). Other important causes include caustic ingestion (especially in low-resource settings), radiation therapy to the chest or neck, surgical anastomosis following esophagectomy or other gastrointestinal surgeries, and post-endoscopic interventions[2]. These benign conditions generally exhibit a slower progression and are more amenable to repeated endoscopic management than their malignant counterparts. In this mini-review, we will focus on benign stricture of the esophagus.

DEFINITIONS USED FOR ESOPHAGEAL STRICTURE

Based on the anatomical and clinical characteristics, esophageal strictures are categorized as simple or complex[6]. This classification helps guide treatment decisions and predict outcomes. A simple esophageal stricture is defined as a narrowing of the esophageal lumen that has the following characteristics: Short segment (< 2 cm), single, relatively straight (non-tortuous), has wide enough diameter to allow passage of a standard adult endoscope (≥ 10-12 mm), responds well to 1-3 sessions of endoscopic dilation and has low recurrence rate after treatment. A complex esophageal stricture has anatomical or clinical features that make it more difficult to treat and more prone to complications and recurrence. A complex esophageal stricture is usually long, has an angulated or tortuous course, has a significantly narrowed lumen or multiple strictures, requires multiple sessions of dilation, and has high recurrence rates. Table 2 enumerates the differences between simple and complex esophageal stricture.

Table 2 Difference between simple and complex stricture.

Feature	Simple stricture	Complex stricture
Length	Usually less than 2 cm	Often more than 2 cm
Shape	Straight	Angulated and/or tortuous
Lumen diameter	≥ 10-12 mm	< 10 mm
Endoscope passage	Usually, possible	Often impossible
Number	Usually, single	Single or multiple
Response to dilation	Good, 1-2 sessions are often enough	Recurrent, requires multiple sessions
Cause	Peptic stricture, esophageal web, Schatzki ring, etc.	Caustic strictures, radiation stricture, eosinophilic esophagitis, etc.

Understanding the differences between refractory and recurrent esophageal strictures is also essential for guiding long-term management and identifying when more aggressive or alternative therapies may be needed (Table 3). A refractory esophageal stricture is defined as failure to achieve successful dilation up to a 14-mm diameter after five sessions performed every 2-3 weeks[7]. Recurrence is defined as the occurrence of symptoms with endoscopic evidence of stricture after achieving an initial diameter of 14 mm[7].

Table 3 Difference between refractory and recurrent esophageal stricture.

Feature	Refractory stricture	Recurrent stricture
Lumen diameter achieved	Never reaches a diameter of ≥ 14 mm after 5 sessions of dilation performed at a short interval	Reaches ≥ 14 mm but later narrows again
Symptom pattern	Persistent dysphagia	Symptom-free interval followed by recurrence
Typical cause	Severe fibrosis, unresponsive inflammation	Incomplete disease control or complex anatomy

MANAGEMENT OF ESOPHAGEAL STRICTURES

Standard management of benign esophageal strictures: Endoscopic dilation

Endoscopic dilation is the standard of care in the management of esophageal strictures, offering effective and immediate relief of dysphagia. The dilation process includes the knowledge of the stricture, types of equipment, and the dilation procedure.

Dilation equipment

Dilation can be performed using two primary types of devices: (1) Bougie dilators; and (2) Balloon dilators (Figure 1). Historically, non-wire-guided bougie dilators were commonly used. However, these have largely been replaced by safer and more precise wire-guided polyvinyl dilators, such as the Savary-Gilliard (SG) system. Balloon dilators have also evolved significantly over time. Modern balloon dilators can be inserted through the working channel of the endoscope [through-the-scope (TTS)] and can be expanded to three incremental diameters during a single procedure.

Figure 1 Savary-Gilliard bougie dilator and controlled radial expansion through-the-score balloon dilators. A: Savary-Gilliard bougie dilator; B: Controlled radial expansion through-the-score balloon dilators.

The key differences between these two modalities lie in the mechanism of force application and visualization. Bougie dilators exert both axial and radial forces as they traverse the stricture, providing a more tactile sense of resistance during the procedure. In contrast, balloon dilators apply only radial force, offering a more uniform and controlled expansion of the stricture, and the process can be directly visualized endoscopically. Each method has its advantages and limitations. Table 4 enumerates the differences between these two types of dilation systems. Although the choice of dilators ultimately depends on the endoscopist's discretion, certain factors can help guide the preference. Balloon dilators are preferable in cases with multiple esophageal strictures of varying diameters, associated gastric cicatrization, or when the distal esophageal anatomy is uncertain. On the other hand, bougie dilators may be favored for long strictures (> 5 cm), cervical esophageal strictures, and when the underlying etiology is caustic injury.

Table 4 It enumerates the difference between bougie and balloon dilators.

Feature	Bougie dilators	Balloon dilators
Mechanism of action	Apply axial/shearing force as they are pushed through the stricture	Apply radial/centrifugal force by expanding within the stricture
Force distribution	Longitudinal, may be uneven and less controlled	Radial and uniform, leading to symmetrical expansion
Need for endoscopic visualization	Not essential	Requires endoscopic access (TTS) or fluoroscopy
Need for guidewire	Required	May or may not require, depending on the type of balloon dilator
Cost	Generally lower (reusable)	Higher (disposable or limited reuse)
Procedure time	Shorter procedure time	Longer procedure time due to multistep inflation
Types	Savary-Gilliard (wire-guided)	TTS balloon

TTS: Through-the-scope.

Bougie dilators

The SG dilator is one of the most widely used bougie-type dilators for endoscopic treatment of esophageal strictures. SG dilators are designed for use over a guidewire threaded through a central lumen. They come in a range of diameters (5-20 mm) and lengths (70 cm and 100 cm), allowing adaptability across various clinical scenarios. A notable feature is the radio-opaque marker at the junction of the tapered tip and shaft, facilitating precise placement under fluoroscopic guidance.

The dilation procedure begins with the insertion of a steel guidewire across the stricture. The guidewire can be placed either endoscopically or fluoroscopically. Once positioned, the SG dilator is advanced gently over the guidewire, passing at least 5-10 cm beyond the stricture (excluding the tapered tip). When performing under fluoroscopic guidance, proper passage is confirmed when the radio-opaque marker has traversed the stricture. A key advantage of the SG system is the tactile resistance it provides during advancement. Additionally, visible blood on the dilator shaft upon withdrawal may signal mucosal injury, prompting cessation of further dilation in the same session.

Balloon dilators

TTS balloon dilators have significantly improved the management of esophageal strictures by enabling direct endoscopic visualization during dilation, increasing both precision and safety, particularly in tight or complex cases. TTS balloons are available in two types: (1) Wire-guided, where a guidewire is first passed through the stricture and the balloon is advanced over it; and (2) Non-wire-guided, where the balloon is directly positioned across the stricture under endoscopic guidance. Both types are effective, with the choice guided by the stricture's characteristics, anatomy, and operator preference.

Available in various diameters (typically 6-20 mm), most modern balloons allow controlled radial expansion (CRE), i.e., inflating into three predefined stages using hydrostatic pressure. Proper positioning of the balloon is critical for successful dilation. Once across the stricture, the balloon is aligned such that the stricture lies centrally between the two ends of the balloon. It is then gradually inflated to the target pressure as per the manufacturer’s specifications, achieving controlled and uniform radial force across the narrowed segment. Further dilation to a larger diameter can be achieved by incrementally increasing the inflation pressure within the safe limits prescribed for that balloon.

CRE balloons are a reliable and predictable tool in therapeutic endoscopy, offering a key safety advantage. Made from high-compliance material, they are engineered to rupture rather than over-expand if excessive pressure is applied. This built-in fail-safe mechanism helps minimize the risk of complications such as esophageal perforation.

DILATION TECHNIQUE

Clinical and imaging evaluation

Evaluation of esophageal strictures starts with a focused history and physical exam, emphasizing dysphagia characteristics and related symptoms. Esophagogastroduodenoscopy is the preferred diagnostic tool, offering visualization, biopsy, and possible treatment[8]. However, for many, contrast study remains the preferred diagnostic modality[9], while computed tomography scans are reserved for select cases and not routinely recommended.

Consent

Endoscopic dilation of esophageal strictures is effective but carries risks, including bleeding, pain, bacteremia, and potentially life-threatening perforation[10]. Informed consent is essential, covering the procedure, risks, expected outcomes, and possible need for repeat sessions. For complex strictures, alternative treatments like stents or surgery should also be discussed.

Patient preparation

Proper pre-procedure preparation for esophageal stricture dilation includes keeping the patient nil per os for 6-8 hours, assessing cardiac and respiratory status, and managing anxiety with counselling. Anticoagulants should be stopped 24 hours prior, with heparin bridging considered for high-risk patients. Low-dose aspirin may often be continued, depending on bleeding risk and clinical need.

Selection of an appropriate dilator

Wire-guided bougie and CRE balloon dilators have similar effectiveness and safety for treating esophageal strictures, with no significant differences in dysphagia relief, recurrence, or complications[11]. However, most published studies have focused on peptic strictures. More recent evidence suggests a potential superiority of bougie dilators in specific contexts. In a study by Singh et al[12], bougie dilators demonstrated significantly higher short-term clinical success at one month (65.6% vs 46.3%, P = 0.01) and better long-term clinical success at one year (86.9% vs 64.2%, P < 0.01) when compared with balloon dilators.

The selection between bougie and balloon dilators is typically not influenced by the underlying cause of the esophageal stricture, except in caustic-induced cases, where bougie dilators are preferred for their tactile feedback during advancement[12,13]. However, several other factors impact dilator choice, especially the presence of multiple strictures with varying calibers, gastric cicatrization, and unclear or unknown distal esophageal anatomy – situations where certain dilators may offer enhanced control or safety. Additionally, the availability of specific dilators and the endoscopist’s experience and preference significantly guide the decision. Ultimately, dilator selection should be individualized, based on the patient's anatomy, clinical context, and procedural objectives.

How much to dilate during the initial session

The choice of dilation diameter in esophageal stricture management depends on several key factors, including: (1) Estimated diameter of the stricture; (2) Length of the stricture; (3) Underlying etiology; (4) Resistance encountered during dilation; and (5) Real-time findings observed during the procedure. Dilation should typically start with a dilator that is 1-2 mm larger than the estimated luminal diameter of the stricture. For simple, short strictures, the lumen can usually be safely dilated up to 15 mm in a single session. However, a more cautious and gradual approach is recommended for complex or tortuous strictures, where the maximum dilation diameter should be limited to 8-12 mm, depending on the patient's tolerance and procedural observations. For narrow, long, tortuous, or filiform strictures, dilation should be even more careful, and should not exceed 9-10 mm in a single session due to the increased risk of perforation.

Safety must always take precedence over speed. In this context, the "rule of three" is particularly imperative, especially for complex strictures or when the procedure is being performed by less experienced endoscopists[14,15]. According to this rule, no more than three sequential dilator size increments should be attempted in a single session to minimize the risk of adverse events.

Frequency of dilation and endpoint

Studies have followed a protocol of performing dilation sessions at intervals of 1-3 weeks[15]. Although there is no universally accepted optimal interval between sessions, most protocols recommend repeating dilation every 2 weeks. This two-week interval strikes a balance by minimizing trauma and rebound fibrosis associated with dilation, while also providing enough time for tissue healing. It reduces the need for emergency or rescue dilations.

These repeat dilations are to achieve an end-point esophageal diameter of 14-15 mm. Dilating beyond 14-15 mm has not demonstrated additional benefits in symptom relief or prevention of dysphagia recurrence and may increase the risk of complications[16,17]. Therefore, 14-15 mm should be considered the target diameter for therapeutic dilation.

MANAGEMENT OPTIONS BEYOND DILATION

Adjunctive therapies with dilation

Adjunctive therapies are often employed alongside endoscopic dilation to improve outcomes in patients with esophageal strictures after failed endoscopic dilation. These therapies aim to reduce stricture recurrence, enhance the effectiveness of dilation, and prolong symptom relief. Common adjunctive approaches include intralesional steroid or mitomycin, incisional therapy, or stenting. These adjunctive therapies are selected based on the stricture’s etiology, complexity, and response to previous treatments. Their use requires careful patient selection and procedural expertise to minimize complications and maximize therapeutic benefit.

Intralesional steroids

Intralesional steroid injection, particularly with triamcinolone acetonide, has emerged as a valuable adjunctive treatment for refractory benign esophageal strictures when dilation alone is inadequate. The earliest evidence came from Gandhi et al[18], who demonstrated symptomatic improvement in six patients with caustic-induced strictures. Subsequent case series by Berenson et al[19] and Zein et al[20] further supported its efficacy in reducing the need for frequent dilations.

Three randomised studies have looked at the efficacy of the intralesional steroids in refractory anastomotic and peptic stricture[21-23]. Two randomized controlled trials focusing specifically on anastomotic strictures yielded conflicting results. In a larger trial of 60 patients post-esophagectomy, Hirdes et al[21] found no significant benefit from intralesional steroid injection in terms of dysphagia relief, number of dilations, or patient satisfaction. In contrast, a smaller study by Pereira-Lima et al[22], involving 19 patients with tighter anastomotic strictures, demonstrated significantly better dysphagia relief at both 1 month and 6 months in the steroid group, though it did not reduce the number of dilations. Another randomized study by Ramage et al[23] focused on peptic strictures and showed that intralesional triamcinolone significantly delayed the need for repeat dilation and reduced the number of dilations required over 6 months.

Multiple case series (eight cases) have examined the efficacy of intralesional steroid injections in managing refractory benign esophageal strictures of various causes[24-31]. One of the most comprehensive evaluations was conducted by Kochhar and Makharia[29], involving 71 patients with strictures of diverse etiologies – corrosive, peptic, anastomotic, and radiation-induced. Tables 5 and 6 summarize all the studies on the role of steroids in benign esophageal stricture[21-31]. Overall, these studies confirmed the beneficial effect of intralesional triamcinolone and support its use in refractory strictures, while the benefit in the treatment-naïve esophageal stricture is equivocal.

Table 5 Characteristics of the studies that evaluated the effect of intralesional steroid in treatment naïve esophageal strictures.

Ref.	Study type and number of patients	Etiology of stricture	Dilator used	Steroid application	Outcome
Miyashita et al[24], 1997	Case series, n = 11	Anastomotic: 11	Balloon	2 mg dexamethasone into each quadrant (post-dilation). After dilation. Unclear repeating schedule	The mean number of dilations decreases significantly after steroid injection (1.1 vs 4.7, P < 0.05)
Orive-Calzada et al[25], 2012	Case series, n = 9	Anastomotic: 2; corrosive: 4; peptic: 3	NA	NA	No difference in mean number of dilations after steroid injection (3.33 vs 3, P = 0.673)
Hirdes et al[21], 2013	RCT, n = 29 in steroid arm	Anastomotic: 29	Bougie	20 mg triamcinolone into each quadrant (pre-dilation). Repeated up to 3 times	The number of patients dysphagia-free at 6 months was not different in the steroid and control group (45% vs 36%, P = 0.46)
Pereira-Lima et al[22], 2015	RCT, n = 10 (steroid arm)	Anastomotic: 10	Bougie	NA	The number of patients dysphagia-free at 6 months was higher in the steroid arm than the control group (62% vs 0%, P = 0.009)
Altintas et al[26], 2004	RCT, n = 10 (steroid arm)	Anastomotic: 1; corrosive: 2; peptic 6; radiation: 1	Bougie	8 mg triamcinolone into each quadrant (post-dilation). Only the first time	Mean periodic dilation index decreases significantly after steroid injection (0.193 vs 0.597, P < 0.05)

NA: Not available; RCT: Randomised controlled trial.

Table 6 Characteristics of the studies that evaluated the effect of intralesional steroid in refractory esophageal strictures.

Ref.	Study type and number of patients	Etiology of stricture	Dilator used	Steroid application	Outcome
Ramage et al[23], 2005	Randomised controlled trial, n = 15 (steroid arm)	Peptic: 15	Balloon	20 mg triamcinolone into each quadrant at the narrowest part (pre-dilation) With each dilation	Number of follow-up dilations, time to first repeat dilation was not different among the two groups (P > 0.05)
Ahn et al[27], 2015	Case series, n = 25	Anastomotic: 1, eosinophilic esophagitis: 3, peptic: 17, radiation: 4	Bougie or balloon	10 mg triamcinolone into each quadrant at the proximal margin and into the stricture segment (post-dilation) with each dilation	Mean PDI decreases significantly after steroid injection (0.58 vs 0.28, P < 0.05)
Kochhar et al[28], 1999	Case series, n = 17	Corrosive: 17	Bougie	10-15 mg triamcinolone at the proximal margin and into the stricture (pre-dilation in 13 patients and post-dilation in 4 patients). Injections repeated if no subjective response at subsequently scheduled session (maximum: 3)	Median PDI decreases significantly after steroid injection (1.67 vs 0.32, P < 0.01)
Kochhar et al[29], 2002	Case series, n = 71	Anastomotic: 19, corrosive: 29, peptic: 14, radiation: 9	Bougie	10 mg triamcinolone into each quadrant at the proximal margin and into the strictured segment (pre-dilation in 63 patients and post-dilation in 8 patients). Injections repeated if no subjective response at subsequently scheduled session (maximum: 4)	Mean PDI decreases significantly after steroid injection (1.24 vs 0.51, P < 0.001)
Lee et al[30], 1995	Case series, n = 31	Anastomotic: 8, corrosive: 1, peptic: 12, pill esophagitis: 1, radiation: 6, sclerotherapy: 1	Bougie or balloon	28 mg triamcinolone into each quadrant at the narrowest region of the stricture (post-dilation) with each dilation	The mean number of dilations significantly reduced with steroid injection (P < 0.05)
Nijhawan et al[31], 2016	Case series, n = 11	Caustic: 11	Bougie	10 mg triamcinolone into the proximal margin of the stricture and the strictured segment (if long stricture) (post-dilation), weekly for 5 weeks	Mean PDI decreases significantly after steroid injection (2.54 vs 0.19, P < 0.001)

PDI: Periodic dilation index.

Administration techniques and dosing protocols vary across studies. Typically, triamcinolone is injected into four quadrants of the stricture, often targeting both the proximal margin and the narrowed segment itself. Reported concentrations range from 10 mg/mL to 40 mg/mL, with total volumes per session varying between 0.5 mL and 2.8 mL. A widely adopted regimen includes injecting 0.5 mL of 40 mg/mL triamcinolone into each quadrant, providing a practical and effective strategy for clinicians. Despite variability, available data consistently suggest that intralesional steroids can reduce stricture recurrence and dilation frequency, making them a valuable tool.

Intralesional mitomycin

Mitomycin C, a chemotherapeutic agent traditionally used in treating malignancies such as esophageal, anal, breast, and bladder cancers, has gained attention for its antifibrotic properties in managing refractory benign esophageal strictures. Its mechanism of action involves inhibition of fibroblast proliferation and collagen synthesis, making it a potential alternative to intralesional steroids in difficult-to-treat strictures. Uhlen et al[32] first reported the benefit of mitomycin C in four patients with refractory strictures. Since then, multiple studies have evaluated its efficacy.

Evidence from two randomized placebo-controlled trials has supported the adjunctive use of mitomycin C with endoscopic dilation[33-35]. These studies showed symptomatic resolution in 80% and 82.6% of patients treated with mitomycin, significantly higher than those who underwent dilation alone[33,34]. A recent meta-analysis further reinforced these findings, reporting a 42% increase in dysphagia resolution rates with mitomycin C use (risk difference: 0.42, 95%CI: 0.29-0.56, P < 0.00001)[36]. Although most of the supporting data[37-40] focus on caustic strictures, there is also emerging evidence of benefit in radiation-induced and anastomotic strictures[41-43]. Table 7 summarizes the available studies on the use of mitomycin in refractory esophageal strictures[33-35,37-43].

Table 7 Characteristics of the studies (with at least 5 patients) that evaluated the effect of mitomycin application for refractory esophageal strictures, n (%).

Ref.	Study type and number of patients	Etiology of stricture	Number of applications	Outcome
Rosseneu et al[37], 2007	Prospective clinical trial, n = 15	Caustic: 9, anastomotic: 9, peptic: 2, Crohn’s: 1, and dystrophic epidermolysis bullosa: 1	Median: 2	Stricture resolution: Complete: 10, partial: 2, no improvement: 3
Gillespie et al[38], 2007	Case series, n = 12	Radiation: 11 and anastomotic: 1	Mean: 1	Stricture resolution: Complete: 11 (91.7), partial: 1 (8.3) and required two additional sessions
Coopman et al[39], 2009	Case series, n = 6	Caustic: 3 and esophageal atresia: 3	Mean: 1.5	All have clinical and endoscopic improvement
Machida et al[40], 2012	Case series, n = 5	Post endoscopic submucosal dissection: 5	Mean: 1.6	All have resolution of symptoms without further dilations
El-Asmar et al[34], 2013	RCT, n = 20 (mitomycin arm)	Caustic: 20	Median: 1	Stricture resolution in 80%
El-Asmar et al[41], 2013	Prospective clinical trial, n = 16	Caustic: 16	Mean: 2.4	Stricture resolution in 81.2%
Nagaich et al[42], 2014	Prospective study, n = 12	Caustic: 12	Mean: 4.75	Increased interval for dilations in all
Sweed et al[35], 2015	RCT, n = 18 (mitomycin arm)	Caustic: 18	Median: 1	Dysphagia resolved in all patients
Bartel et al[43], 2016	Case series, n = 9	Anastomotic: 3, radiation: 3, caustic: 2, anastomotic + radiation: 1	Not available	Mean periodic dilation index decreased from 1.53 to 0.39, P = 0.01
Ghobrial et al[33], 2018	RCT, n = 60 (mitomycin arm)	Caustic: 60	Mean: 3.25	Stricture resolution in 81.6% patients compared to only 40% in the control arm (P < 0.0001)

RCT: Randomised controlled trial.

Mitomycin C has been applied using varied techniques and concentrations. Doses have ranged from 0.1 mg/mL to 1 mg/mL, with 0.4 mg/mL being the most frequently used. The drug may be administered topically by applying gauze or pledgets soaked in mitomycin to the dilated stricture for 2-5 minutes, or via direct intralesional injection after dilation. Despite promising results, standardized protocols are lacking, and further large-scale, high-quality studies are needed to define the optimal dosing, method of delivery, and patient selection for mitomycin C in refractory esophageal strictures.

Incisional therapy has emerged as a valuable endoscopic option for the management of benign refractory esophageal strictures, particularly when conventional dilation fails to provide sustained relief. This technique is typically performed using either a standard needle-knife or an insulated-tip electrosurgical knife, and is especially effective in short, fibrotic, and elevated strictures such as Schatzki rings and anastomotic strictures. The procedure involves making 4-8 radial incisions into the stricture under direct visualization, taking care to limit the depth of incisions to within the esophageal wall. In some cases, residual fibrous tissue between the incisions may be excised to enhance luminal expansion.

Ideal candidates for this approach are those with fibrotic strictures measuring 1-2 cm in length. Immediate clinical success rates reported across studies are high, ranging from 81% to 100%, while long-term symptom relief is achieved in approximately 44%-93% of the cases[44-53]. However, complication rates – most commonly bleeding and perforation – have been reported in 3.5%-18% of patients, underscoring the need for careful patient selection and procedural expertise.

Table 8 summarizes key studies evaluating incisional therapy for anastomotic and short fibrotic strictures[44-53]. While a few small studies and case reports have explored the combination of incisional therapy with balloon dilation performed during the same session, current evidence is insufficient to establish the safety and efficacy of this combined strategy.

Table 8 Studies that evaluated the incisional therapy for esophageal strictures.

Ref.	Number of patients	Etiology of stricture	Clinical success at follow-up	Follow-up duration (months)
Treatment naïve
Burdick et al[44], 1993	7	Schatzki ring	85.7%	36
Disario et al[45], 2002	11	Schatzki ring	36%	72
Schubert et al[46], 2003	15	Anastomotic strictures	93%	23
Hordijk et al[47], 2009	31	Anastomotic strictures	67.7%	6
Lee et al[48], 2009	24	Anastomotic strictures	87.5%	24
Treatment refractory
Brandimarte et al[49], 2002	6	Anastomotic strictures	36%	24
Simmons et al[50], 2006	9	Anastomotic strictures	44.4%	14
Hordijk et al[51], 2006	20	Anastomotic strictures	60%	12
Muto et al[52], 2012	32	Anastomotic strictures	62%	12
Tan and Liu[53], 2016	13	Anastomotic strictures	60%	24

SEMS

Esophageal stents can be used in the management of benign refractory esophageal strictures as a treatment option. The most commonly used stents nowadays are fully-covered SEMS or lumen apposing metal stents. These stents provide continuous radial pressure, helping to maintain esophageal patency and reduce the need for frequent dilations. However, their use is associated with complications such as stent migration, chest pain, reflux, and granulation tissue formation. As a result, SEMS are typically considered a temporary measure and are left in place for a limited duration (usually 4-8 weeks). For strictures longer than 5 cm or caused by ischemic injury, stenting for 8-16 weeks is considered. A systematic review and meta-analysis of 18 studies evaluated the outcomes of SEMS in refractory esophageal strictures[54], reporting a pooled clinical success rate of 40.1%, a migration rate of 31.5%, and an adverse event rate of 21.9%. Additionally, several case series (thirteen cases) have demonstrated success rates ranging from 0% to 60% with SEMS placement in refractory strictures[55-67]. Although the clinical improvement may be modest, it can be meaningful for patients who require repeated dilations. To optimize outcomes and minimize risks, careful patient selection and close follow-up are essential. Table 9 summarizes the available studies on the use of SEMS in benign esophageal strictures[55-67].

Table 9 Studies (with at least 5 patients) that evaluated the self-expandable metal stents in benign esophageal strictures, n (%).

Ref.	Study type, number of patients	Etiology of stricture	Median duration of stent (days)	Clinical success	Complication rates
Song et al[55], 2000	Prospective, n = 25	Peptic: 1 (4), caustic: 22 (88), radiotherapy: 1 (4), other: 1 (4)	29	12 (48)	17 (68)
Kim et al[56], 2009	Retrospective, n = 51	Peptic: 1 (2), caustic: 44 (86), radiotherapy: 2 (4), anastomotic: 2 (4), other: 3 (6)	56	13 (26)	14 (27)
Bakken et al[57], 2010	Retrospective, n = 25	Peptic: 7 (28), radiotherapy: 8 (32), anastomotic: 10 (40)	67 (0-279)	13 (52)	5 (20)
Eloubeid et al[58], 2011	Retrospective, n = 19	Peptic: 4 (21), caustic: 2 (11), radiotherapy: 2 (11), anastomotic: 9 (47), other: 2 (11)	64 (6-300)	4 (21)	5 (26)
Hirdes et al[59], 2012	Prospective, n = 15	Peptic: 6 (40), caustic: 3 (20), radiotherapy: 2 (13), other: 4 (27)	61 (13-222)	0	5 (33)
Liu et al[60], 2012	Retrospective, n = 24	Anastomotic	74 (63-84)	18 (75)	0
Canena et al[61], 2012	Prospective, n = 30	Peptic: 7 (23), caustic: 3 (10), radiotherapy: 2 (7), anastomotic: 13 (43), other: 5 (17)	90	8 (27)	2 (7)
Chaput et al[62], 2013	Prospective, n = 41	Peptic: 16 (39), caustic: 3 (7), radiotherapy: 8 (20), anastomotic: 12 (29), other: 2 (5)	58 (20-140)	21 (51)	5 (12)
Dan et al[63], 2014	Retrospective, n = 17	Peptic: 2 (12), radiotherapy: 3 (18), anastomotic: 9 (52), other: 3 (18)	71 (1-65)	5 (29)	0
Yang et al[64], 2017	Retrospective, n = 5	Peptic stricture: 2, anastomotic stricture: 3	60 (40-90)	5 (100)	1 (20)
Santos-Fernandez et al[65], 2017	Retrospective, n = 9	Caustic: 2, radiation/anastomotic: 7	67.6 (mean)	3 (33)	2 (22.2)
Lu et al[66], 2019	Retrospective, n = 20	Peptic, caustic, radiotherapy, anastomotic	29 (7-67)	7 (35)	9 (47)
Mahmoud et al[67], 2023	Retrospective, n = 15	Peptic: 4, radiation: 3, anastomotic: 8	119 (49.5-352)	14 (93)	Not available

SEMS, though an attractive option for esophageal strictures, is associated with significant long-term complications. In contrast, biodegradable stents (BDS) have emerged as a promising alternative. These stents, typically made from materials such as polydioxanone or poly-L-lactic acid, degrade gradually via hydrolysis over several weeks, eliminating the need for endoscopic removal and potentially reducing long-term adverse events associated with permanent metal stents. The SX-ELLA Stent Esophageal Degradable BD (Hradec Kralove, Czech Republic), composed of polydioxanone monofilament, maintains radial force for approximately 6 weeks and undergoes complete disintegration by 12 weeks post-placement. Theoretically, BDS offers the mechanical benefits of SEMS with fewer complications; however, clinical success remains variable, ranging from 15% to 60 % (Table 10)[68-73]. A meta-analysis by Fuccio et al[54] evaluating different stents for benign esophageal strictures found that the clinical success of BDS (32.9%; 95%CI: 23.1%-44.1%) was comparable to SEMS (40.1%) and self-expanding plastic stents (SEPS) (46.2%). Notably, stent migration was significantly lower with BDS (15.3%) compared to SEMS (31.5%) and SEPS (33.3%). Despite only marginal benefits and variable efficacy, current BSG guidelines recommend BDS in selected patients (low-quality evidence, weak recommendation). Their use, however, remains limited by high cost and restricted availability. Therefore, BDS may be considered in refractory cases unresponsive to other modalities to reduce dilation frequency.

Table 10 Studies that evaluated the biodegradable stents in benign esophageal strictures, n (%).

Ref.	Study type, number of patients	Etiology of stricture	Technical success	Clinical success	Complication rates
Repici et al[68], 2010	Prospective, n = 21	Peptic: 7 (33), caustic: 2 (10), radiotherapy: 5 (24), anastomotic: 5 (24), other: 2 (10)	21 (100)	9 (43) at 1 year	3 (14)
van Boeckel et al[69], 2011	Prospective, n = 18	Peptic: 6 (33), caustic: 2 (11), radiotherapy: 2 (11), anastomotic: 5 (27), others: 3 (16)	15 (85)	6 (33) at 3 months	6 (33)
van Hooft et al[70], 2011	Prospective, n = 10	Anastomotic: 10 (100)	10 (100)	6 (60) at 6 months	6 (60)
Hirdes et al[71], 2012	Prospective, n = 28	Peptic: 9 (32), caustic: 2 (7), radiotherapy: 3 (11), anastomotic: 7 (25), others: 7 (25)	28 (100)	7 (25) at 6 months	8 (29)
Karakan et al[72], 2013	Prospective, n = 7	Caustic: 7 (100)	7 (100)	2 (29) at 60 weeks	3 (43)
Kochhar et al[73], 2017	Prospective, n = 11	Caustic: 13 (100)	13 (100)	2 (15.4) at 1 year	7 (54)

PERORAL ENDOSCOPIC TUNNELLING AND RESTORATION OF THE ESOPHAGUS

Peroral endoscopic tunnelling and restoration of the esophagus (POETRE) is an advanced endoscopic technique modifying the standard peroral tunneling approach. It involves the creation of a submucosal tunnel to traverse or dissect through a completely occluded or severely narrowed segment of the esophagus. This method enables the endoscopist to reestablish esophageal continuity and restore luminal patency in cases where traditional methods like dilation or stenting are unsuccessful or not feasible.

Babich et al[74] were the first to describe the use of a retrograde submucosal tunneling technique in managing a case of a completely occluded esophagus. Building on this approach, Wagh et al[75] applied the technique to a complex esophageal stricture and formally named the procedure POETRE. Since then, several other case reports have demonstrated the feasibility and clinical utility of POETRE, incorporating various modifications to adapt to individual anatomical and pathological challenges[76-78]. POETRE represents a promising and minimally invasive option for carefully selected patients with refractory or completely obstructed esophageal strictures. Although the technique appears promising, the available literature is limited to case reports. Moreover, it is technically demanding and requires expertise in third-space endoscopy, and is currently performed only in a few specialized centers worldwide.

SELF-DILATION

Self-dilation is a reliable and safe method to address refractory esophageal strictures. Reports describe self-dilation dating back to 1961 from Wooler[79] on one patient and by Palmer[80] on three patients. Over the next few decades, several studies reported the effectiveness of self-bouginage. In 1984, Grobe et al[81] described successful self-dilation in 12 patients with peptic stricture. Clinical improvement was noted in 100% of the patients, with complete relief of dysphagia in 75% patients over a mean follow-up of 4.8 years. Bapat et al[82] in a study of 51 patients of caustic-induced esophageal strictures, followed the patients with daily self-dilation for 3 months, followed by once-a-week lifelong. On long-term follow, 97.5% (39 of 40) patients were symptom-free, while only one patient had recurrence of dysphagia and required retraining of self-dilation. Similarly, Davis et al[83] in a large study of 158 patients with anastomotic strictures after esophagectomy, described the successful use of self-dilation. Over a median follow-up of 10 years, most patients were satisfied with their ability to eat without any adverse effects.

Self-dilation appears to be the most economical method to treat refractory strictures with good efficacy and long-term outcome. Studies have reported a successful long-term outcome ranging from 75% to 97%[81,83]. However, appropriate patient selection is crucial for optimal results. The best candidates are well-informed and motivated individuals with simple yet refractory strictures. The ideal strictures should be typically short (< 3-5 cm), straight, non-angulated, without any pre-stricture esophageal dilatation. The location of the stricture, whether proximal or distal esophagus, does not significantly influence the outcome, although proximal strictures are generally easier to dilate. While the etiology of the stricture does not appear to affect short-term success, caustic strictures often require a longer duration of self-dilation compared to other causes. Figure 2 describes the steps of self-dilation.

Figure 2 Steps of the self-dilation and follow-up protocol.

SURGERY

Surgical intervention is considered a last-resort treatment for patients with refractory benign esophageal strictures that do not respond to endoscopic therapies. Common surgical approaches include esophageal resection with reconstruction, stricturplasty, and bypass procedures. The choice of surgery depends on several factors, including the length and location of the stricture, the presence of adhesions, the patient’s overall risk profile, and the surgical expertise available.

Although surgical treatment can lead to significant long-term symptom relief and improved QoL in well-selected cases, it carries a higher risk of morbidity and mortality compared to endoscopic options. Moreover, it is a technically difficult procedure as surgery usually requires the opening of the thorax or abdomen based on the location of esophageal strictures. Therefore, surgical management should be considered only after thorough evaluation by a multidisciplinary team and when less invasive options have failed.

DILATING ANATOMICALLY DIFFICULT STRICTURES

Strictures at the upper and lower esophageal sphincter (LES) present unique challenges due to their anatomical location and critical functional roles. Upper esophageal sphincter strictures are particularly difficult to manage owing to limited endoscopic maneuverability, a higher risk of aspiration due to proximity to the cricopharyngeus muscle, and challenges in stent anchoring. Management requires a cautious, staged approach with emphasis on airway protection–ideally achieved through endotracheal intubation before dilation. When procedures are performed under sedation, fluoroscopic guidance for guidewire placement and bougie dilation may help enhance safety and precision. In cases requiring stenting, specialized cervical SEMS with short proximal flares are preferred. Despite ongoing concerns with stent migration, distal-end fixation may be used instead of traditional proximal fixation to improve stability.

Strictures at the LES carry their own set of limitations, including an increased risk of gastroesophageal reflux and higher recurrence rates due to reflux-induced injury. After dilation, the need for PPI therapy should be assessed individually to reduce the recurrence risk. When stents are necessary at this location, SEMS with anti-reflux valves are preferred. To prevent stent migration, proximal fixation using devices like the OVESCO stent-fix system may be employed.

ALGORITHM APPROACH TO MANAGEMENT OF REFRACTORY BENIGN ESOPHAGEAL STRICTURE

Endoscopic dilation is the first-line treatment for benign esophageal strictures. Both balloon and bougie dilators are effective in the majority of simple strictures, and either can be used as the initial approach. The choice between the two may be guided by factors such as stricture etiology and length, instrument availability, and operator preference. While most benign strictures respond well to dilation, refractory/recurrent benign esophageal strictures (RBOS) pose a significant therapeutic challenge. A retrospective multicentre analysis of 70 patients with RBOS reported poor long-term symptom resolution in fewer than one-third of patients, despite an average of 15.5 dilations per patient over a mean follow-up of 43.9 months[84].

Given these limitations, various adjunctive treatment modalities have been explored as discussed in detail previously. However, no single approach has proven superior. The choice of adjunctive therapy depends on multiple factors, including stricture etiology, anatomical characteristics (such as length and location), endoscopist experience, prior interventions, and treatment cost. An algorithmic approach to the management of RBOS is outlined in Figure 3, providing a structured pathway based on individual patient and stricture characteristics.

Figure 3 Algorithm for the management of recurrent/refractory benign esophageal stricture. SEMS: Self-expanding metal stents; ES: Esophagus.

CONCLUSION

Endoscopic dilation is the cornerstone of treatment for benign esophageal strictures, offering symptomatic relief and improved swallowing in the majority of cases. These strictures typically respond well to serial dilations using either balloon or bougie dilators. While most benign strictures are successfully managed with dilation alone, a subset of patients develops refractory strictures. The options for adjunctive therapies include intralesional steroid or mitomycin injection, incisional therapy, temporary stent placement, self-bouginage, endoscopic restoration of the esophagus, in rare cases, surgical intervention. The choice of adjunctive therapy is dictated by characteristics, i.e., anatomy, etiology, prior adjunctive therapy failure, availability, and patients’ preference. A relatively short, non-angulated and proximally located stricture can be managed with self-bouginage. Long segment or multiple strictures should be considered for adjunctive intra-lesional therapies. Patients with prior adjunctive failure should be considered for SEMS or BDS. Availability of a plethora of adjunctive therapies suggests the uncertainties of each therapy and the complexities involved in the management of these strictures. A careful selection of patients and appropriate technique can optimize the outcome in these patients.

Future directions in the management of refractory esophageal strictures focus on improving long-term outcomes, reducing recurrence, and minimizing the need for repeated interventions. The technological advancement should focus on the next-generation BDS with more predictable degradation profiles and reduced migration risk. Innovative drug-eluting stents for these strictures will hold promise for broader clinical use. Regenerative medicine approaches, such as the use of stem cell therapy and tissue-engineered scaffolds, are being explored to promote mucosal healing and restore normal esophageal architecture. Artificial intelligence-assisted dilation planning can help in optimizing the choice of adjunctive therapy. Personalized treatment algorithms based on stricture etiology, molecular markers, and patient-specific factors are likely to guide future management. With technological advanceme multidisciplinary approach combining endoscopic innovation, pharmacologic modulation, and regenerative strategies is expected to redefine the management landscape of refractory esophageal strictures.